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that space and ram it well down. The surface having been made 
smooth, spread the cement, set the bricks and grout with liquid 
cement mortar made of cement one part and sand two parts.. 
Both sand and cement must be sifted, and the mortar must be 
very liquid. Over this foundation build up a single-brick-thick 
work—41% inches—to the height required. Round off the angles 
and corners inside, and have the floor sloping from every direction 
into one corner. 
This favours the drainage of the liquid, which can be bailed 
out with the dipper, and dried with a sponge. Before the cement is 
quite set it is found advisable to blow dry cement and rub it in so 
as to give a smooth polish to the surface. For that purpose use a 
wood float and finish off witha steel trowel. The top of the walls is 
also capped with cement. 
At intervals, on the top of the walls, small brackets are pro- 
vided, which help in making fast the false head which keeps the 
riare or skins and seeds submerged. Instead of having the bottom 
slope converging to one point inside into a cup or pit, a two-inch 
brass tap is sometimes inserted into the wall, flush with the lowest 
corner, and the liquid can be run out, without pumping or syphon- 
ing, which the other alternative would necessitate. In that case 
a small cement gutter with a gradual fall towards an underground 
tank, whence it is pumped out, is provided along the line of vats. 
Although this appears to be a convenient method of emptying the 
vats, yet some object to it on the ground that there may be a danger 
of the taps getting knocked out and causing a leakage, or of the 
underground tank requiring frequent and careful cleansing, thus 
involving extra work. 
The quality of the cement used is not immaterial. Of these 
there are two kinds—the “quick-setting” and the slow-setting”’ 
cement. The former are generally natural cements, containing var- 
iable proportions of lime; whereas the slow-setting cements are 
generally artificially manufactured with definite proportions of lime, 
which varies from 58 to 63 per cent., and are burnt without excess. 
It is said that this regularity of composition, and the way they are 
manufactured, insures their more lasting properties. Slow-setting 
cements containing less lime than some of the quick-setting ones, 
all the lime is taken up by the clay and transformed into aluminate 
cf calcium, and no free lime is left uncombined, which would, in con- 
tact with wine, rob it of some of its natural acids and cause it to 
go flat. 
When cement vats are ysed for storing wine, a roof is provided 
in the shape of a vault, and a manhole made of cast-iron, with a 
tight-fitting door, is set in the structure. It is also sometimes ad- 
visable to line the inside with glazed glass tiles. The St. Gobain 
